claire is absolutely correct. none could have explained better. await and wait for can be used interchangeably and no, it has nothing to do with american or british english. btw, i use await and know many a few who do the same. I dont buy that its archaic.

Await = wait for. The difference in structure is that 'await' requires no preposition. I'll await you = I'll wait FOR you. However, as israelphoenix says, 'await' is completely archaic. It might still be used by poets but I wouldn't concern yourself with it.

Here again is an example of British and American English. British English would say, " I will await your calling." (correct me if you are British) American English would say, I will wait for you to call. I think await is more formal or older English. It is seldom used in America unless one is being unusually posh or silly.